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Radiation exposure and Mission Strategies
for Interplanetary Manned Missions (REMSIM) 总被引：1，自引：0，他引：1
C. Cougnet N. B. Crosby S. Eckersley C. Foullon V. Guarnieri S. Guatelli D. Heynderickx A. Holmes-Siedle C. Lobascio S. Masiello P. Nieminen G. Parisi P. Parodi M. A. Perino M. G. Pia R. Rampini P. Spillantini V. Tamburini E. Tracino 《Earth, Moon, and Planets》2004,94(3-4):279-285
Cosmic radiation is an important problem for human interplanetary missions. The “Radiation Exposure and Mission Strategies for Interplanetary Manned Missions–REMSIM” study is summarised here. They are related to current strategies and countermeasures to ensure the protection of astronauts from radiation during interplanetary missions, with specific reference to: radiation environment and its variability; radiation effects on the crew; transfer trajectories and associated fluences; vehicle and surface habitat concepts; passive and active shielding concepts; space weather monitoring and warning systems. 相似文献
107.
We examine the potential contamination of cometary nuclei through impacts from asteroidal origin meteoroids. The paper uses
a simple model and has the goal of determining whether asteroidal contamination is potentially significant. We assume a meteoroid
power law mass distribution with index values in the range from s=1.83 to s=2.09. We used maximum and minimum models which we believe will bracket the true meteoroid mass distribution. We identify
those comets which are expected to be most significantly contaminated, and find values of up to 3.6 kg of asteroidal meteoroid
impact per square meter of the cometary surface per orbital revolution. This is less than the expected mass loss per perihelion
passage for most comets. Therefore any remnant effects of the contamination will depend on the penetration depth of the meteoroids
in the cometary nucleus, and possibly on the distribution of active and inactive areas on cometary nuclei. We present a simple
model which suggests that even small meteoroids will embed relatively deeply into a cometary nucleus. 相似文献
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The concept of closest approach is analyzed in Hill’s problem, resulting in a partitioning of the position space. The different
behavior between the direct and retrograde motion is explained analytically, resulting in a simple estimate of the variation
of Hill’s periodic and quasi-circular orbits as a function of the Jacobi constant. The local behavior of the orbits on the
zero velocity surfaces and an analytical definition of local escape and capture in Hill’s problem are also given. 相似文献
110.
The experimental data obtained in transit observations of the extrasolar planet HD 209458b and their comparison with theoretical inferences have led to the conclusions that HD 209458b (and other similar hot jupiters) is of a (mainly) hydrogen nature and that these objects probably possess strong magnetic fields. The results of the studies of HD 209458b and prospects for searches for the transits of other extrasolar planets are considered in detail. 相似文献